climated to humid West Africa, is negated by finding it in Sudan 

 localities with long, severely hot, dry seasons. The Texas fever 

 tick occiirs in the Sxadan in areas with from 800 mm. to 1500 mm. 

 annual rainfall. 



The ecology of B. annulatus is unstudied in Africa and the 

 results of research on this subject are awaited with considerable 

 interest. In North and Central America, B. annulatus is entirely 

 a tropical and subtropical tick that dies~out when introduced 

 into the northern states. 



DISEASE RELATIONS 



Unstudied in Africa. B. annulatus in America is the famed 

 vector of Texas fever of cattle ^Babesia bigemina ) . 



REMARKS 



Minning (1934-) considered West African populations to differ 

 from New World B. annulatus and called them B. congolensis . N\i_ 

 merous B, annulltus specimens from the Unitect States and Central 

 Araerica'have been examined in collections of British Museum (Natural 

 History), Rocky Mountain Laboratory, Museum of Con^jarative ZoBlogy, 

 as well a^ Louisiana material kindly presented by Dr. F. C. Bishopp 

 from United States Department of Agricultvire collections. None of 

 these can be distingviished from African "B. congolensis *. 



The chief characters presented for differentiating males are 

 the pointed outer spur of coxa I of "B. congolensis * and the blunt 

 outer spur of coxa I of B. annulatus ." In a few African specimens 

 this spur is blimt, in many American specimens pointed. The 

 American specimens in the Nuttall collections at British Museum 

 (Natural History) are mostly blunt. spurred with few pointed- spur 

 specimens, but those at the Rocky Mountain Laboratory in Montana 

 are almost entirely pointed- spurred. Specimens from Louisiana 

 in the present collection have pointed spurs. It is evident, 

 therefore, that this character is a variable one with no diagnostic 

 significance as to species. The shape of the eyes of African and 

 American specimens is similar. Examination of other so called dif- 

 ferentiating characters has also failed to reveal differences. 



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